Assume for a moment the GOP presidential primary comes down to a battle between Newt Gingrich and Mitt Romney. Ron Paul is certainly going to make things interesting and maybe another candidate will catch lightning in a bottle in one state or another. But in a Gingrich-Romney heavyweight bout, the practical realities of the delegate-gathering process may play out like a three-act drama that goes something like this:

Newt jumps out in front in January with a clutch of early wins, including Florida’s winner-take-all primary. But this isn’t a lethal blow to Romney because of new GOP delegate rules this year (see below).

Mitt Romney’s superior organization and funding brings him back to an even keel with Gingrich during massive Super Tuesday voting in early March.

Both candidates, hoovering up support from former foes who have left the race, enter a final showdown for the nomination in the last weeks of March and early April, before the primaries turn to winner-take-all votes.

So what makes this year’s fight likely to be so protracted? In a nutshell: proportional representation of GOP delegates from early voting states. Before the whole nominating process began, Republicans decided that this year, instead of their typical winner-take-all formula, states holding their primaries before April will award delegates to candidates based on the amount of votes received (although the specifics of said apportionment are up to the states, according to the Republican National Committee’s memo on the subject.)

(Before you dismiss this as political mumbo jumbo, remember that Barack Obama managed to beat Hillary Clinton in 2008 at least in part because his campaign outplayed hers in the sometimes-obscure hunt for delegates.)

(And another parenthetical: The GOP’s decision to try proportional representation has Democratic strategists like Paul Begalalicking their chops because they believe it allows the party’s more extreme candidates the opportunity to hang around longer.)

"To much fanfare, the RNC last year voted to move the first contests later in the year, with only Iowa, New Hampshire, South Carolina and Nevada allowed to have caucuses and primaries in February. All states scheduling contests before April 1 were required to allocate convention delegates by proportional representation instead of the winner-take-all rule.

These rules were designed to avoid an early victory for a candidate who might secure the nomination by stringing together a series of low-plurality wins. That’s what happened in 2008, when John McCain in early February became the de facto nominee despite failing to win a majority of the vote in nearly any of the party’s contests at the time. His early knockout victory contributed directly to reduced participation and media attention in remaining Republican primaries, in sharp contrast to the spirited Democratic contest that continued into June."

What this means: The past rules of GOP political gravity don’t necessarily apply in 2012. A sweep in early states by one candidate won’t put the others as far behind as it once would have - since they can still eke out delegates and go on to fight another day on more hospitable turf.

So, what does the early voting turf look like? Here’s the first group of states casting ballots.

Iowa on Jan. 3 with 28 delegates. New Hampshire on Jan. 10 with 12 delegates (50 percent penalty). South Carolina on Jan. 21 with 25 delegates (50 percent penalty). Florida on Jan. 31 with 50 delegates (50 percent penalty). Nevada, Maine, Minnesota, Colorado, Michigan, and Arizona will vote in February, followed by Washington on March 3. Total delegates at stake up to this point: 345.

Note: “50 percent penalty” indicates that the delegate count for that state has been halved - the reduced number is shown - as a penalty for scheduling its voting ahead of its original assigned date. Florida has maintained its winner-take-all status against party rules.)

Right now, Gingrich is heavily favored in Iowa, South Carolina and Florida, with Romney well in the lead in New Hampshire and Nevada. In past years, that kind of positioning would seem to be a boon (and almost a kill shot) for Gingrich.

But this year, the rules make that nigh impossible. Gingrich is polling in the 30 to 40 percent range in the early states. If those polls translate into actual voting numbers, he’ll have perhaps an 80 delegate edge (or about 6 percent of the total needed to win the nomination) coming out of the early contests - and that’s assuming he gets a sizable bump from all 50 Florida delegates.

That means Mitt Romney will still be very much in the hunt, especially when organization comes most acutely into play in the next phase of the campaign. Here are all of the “Super Tuesday” states that will be voting on March 6, 2012:

This is where Mitt Romney could make serious hay, no matter the poll numbers. Winning 11 primaries on a single day without serious organization and funds would be a historic feat. As Romney backer and powerful GOP moneyman Vin Webertold The New York Times, “There are reasons we call things ‘conventional’ — because they work.”

However, once again, proportional representation of delegates likely would only get Romney back to an even tilt with Gingrich. That gets us into the third phase of the voting - from Super Tuesday through the first big group of winner-take-all states in April. That's 16 states with 655 delegates.

With a potentially fragmented delegate picture heading into April, it appears that if Romney can hang even with Gingrich up to this point, the map will then begin to favor him. It gets decidedly more Eastern - in fact, there’s only one state (Wisconsin) voting in April that isn’t within a cheap flight of Massachusetts.